Surgical / Interventional

Most everyone has back pain at some point in their lives. At any given time, twenty-five percent of the population report having low back pain.1 Forty-three percent of the population report having neck pain.2

Fortunately, most cases of spine-related pain resolves within a few weeks to months.3 Some people, however, continue to have pain and it doesn’t go away. Healthcare providers consider pain to be ‘chronic’ when it lasts longer than six months. Chronic low back pain affects about 10% of the population.4 Chronic neck pain affects 22% of women and 16% of men.2

Patients with chronic back and neck pain commonly seek care with interventional pain physicians and spine surgeons. Interventional pain physicians are typically anesthesiologists or physiatrists who have obtained specialized training in providing interventional procedures like epidural steroid injections, nerve blocks, rhizotomies, and implantable pain control devices. Spine surgeons are typically either orthopedic surgeons or neurosurgeons who have developed a subspecialty in spine-related surgery.

Most patients assume that the healthcare they receive when sick or injured is effective. Chronic pain patients are no different and assume that procedures performed by interventional pain physicians and surgeons are effective. Of course, such interventional and surgical procedures can reduce pain. However, it’s important to know how often such procedures are effective.

Outcome research on health-related procedures demonstrates effectiveness by taking the average outcome of a given procedure. The average outcome is a way to estimate how effective a procedure is when individual patient results vary. That is to say, nothing works every time it is performed. Sometimes, patients are helped by a procedure and sometimes, of course, patients are helped only a bit and some are not helped at all, even when getting the same procedure. The average outcome is a way to estimate how effective the procedure is overall.

Sometimes, researchers compare the average outcome of a procedure with the average outcome of a sham procedure. A sham procedure is a feigned procedure where the patient is unaware that it isn’t the real thing. A sham procedure is the procedural equivalent of a placebo in a drug trial. Sometimes, it is too technically difficult or unethical to perform a sham procedure when doing research. So, researchers then compare the average outcome of the procedure in question to the average of how patients do when getting no treatment whatsoever or when getting ‘treatment as usual,’ which is different from the procedure being studied.

It is important to know something about how effective interventional pain procedures and surgeries are. The following information is a review of the research literature on their relative effectiveness.

Epidural steroid injections

Research on the outcomes of epidural steroid injections consistently shows that they are no more effective on average than injections filled with placebo.5, 6, 7, 8

Rhizotomy

In a well designed study, Van Wijk, et al.,9 tested rhizotomies, or radiofrequency neuroablation, against a sham procedure. They randomized patients into two groups – 40 patients receiving the real rhizotomy and 41 patients receiving the sham rhizotomy. The evaluators and the patients did not know which procedure they received. The investigators found no difference between the two groups in pain levels, activity levels, or intake of analgesic medications.

These results echoed a previous, double-blind study of rhizotomy versus sham rhizotomy.10 This earlier study did not find any significant difference between the two groups as well.

Spine surgeries

There are few studies on the effectiveness of back surgeries for chronic back pain. Of the available studies, the outcomes are mixed. In their attempt to review the research, Mirza and Deyo11 found only five published, randomized clinical trials for fusion surgery. Two had significant methodological problems, which prevented them from drawing any conclusions. One of the remaining three showed that fusion surgery was superior to conservative care. The other two compared fusion surgery to a brief educational class on self-care for back pain. These two studies found no differences between the two groups at one and two year follow-up periods.

In a large clinical trial, Weinstein, et al.,12 compared patients who received surgery with patients who did not receive surgery and found no difference on average. They followed up with the patients two years later and again found no difference between the groups. However, in a later study, they showed that the surgical patients had less pain on average at a four year follow-up period.13

In their review of the literature, Gibson & Waddell14 concluded that there is only minimal evidence that lumbar surgeries are effective in reducing low back pain.

Implantable pain control devices

Research on spinal cord stimulators suffers from poor quality studies. A number of reviews of these studies show that there is limited evidence to support the effectiveness of spinal cord stimulator implants.15, 16, 17

Research on the effectiveness of intrathecal drug delivery systems (aka “pain pumps”) also suffer from poor quality. In their review, Turner, Sears, & Loeser18 found that intrathecal drug delivery systems were modestly helpful in reducing pain. However, because all studies are observational in nature, support for this conclusion is limited.19

Murray J. McAllister, PsyD, is the executive director of the Institute for Chronic Pain (ICP). The ICP is an educational and public policy think tank. Its mission is to lead the field in making pain management more empirically supported. Additionally, the ICP provides Academic quality information on chronic pain that is approachable to patients and their families. Dr. McAllister is also the clinical director of pain services for Courage Kenny Rehabilitation Institute (CKRI), part of Allina Health, in Minneapolis, MN. Among other services, CKRI provides chronic pain rehabilitation services on a residential and outpatient basis.